Vapor-rectifier.



BEST AVAlLABLE UNITED STATES PATENT OFFICE.

ALEXANDER CH UROHYVARD, OF NEW' YORK, N. Y., ASSIGNOR TO GENER ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

VAPOR-RECTIFIER.

Specification of Letters Patent.

Patented Dec. 18, leoe Application filed April 19,1905. Serial No. 256,485.

To (ZZZ whom it may concern:

Be it known that 1, ALEXANDER Cannon- WARD, a citizen of the United States, residing at New York, county of New York, State of New York, have invented certain new and useful Improvements in Vapordtectifiers, of which the following is a specification.

The use of mercury rectifiers for producing unidirectional current of a voltage low enough to charge a storage battery consisting of only a few cells involves the difficulty that the rectifier will not readily start on an alternating voltage low enough to give the desired direct-current pressure at the load. Furtheri'nore, a rectifier so connected cannot be readily started from the direct-current end, as the voltage of the few storage-cells is not sullicient to maintain a starting-arc in the rectifier-tube. To overcome this difliculty, I provide an automatic reactance device in series with one of the rectifier-leads, so that a relatively high voltage-as, for instance, one hundred and ten voltsmay be impressed on the rectifier-anodes at starting, but whereby the rectifier-voltage is immediately cut down as soon as current begins to flow, so that the direct current delivered by the rectifier has a low pressure as, for instance, eight volts and is consequently suitable for charging a small number of storagecells connected in series.

My improved system also includes means whereby the rectifier may be started on a re sistance-load and whereby the battery 11 .1, be subsequently substituted for the resistance, as I find that such an arrangement materially assists the starting operation.

In the drawing forming a part of this specification the mcrcury-rectifier tube 1 is provided with anodes 2- and 3, which are connected, respectively, to the mains 4 and 5 of an alternating-current circuit supplied with current at a commercial volta e and frequency. Two reactance-coils and 7 are connected in series across the anode connections, and a third reactance-coil 8 is LOllllQCted in series with i ml is The rectifier 1 is provided with 2. incl cathode 11 and an auxiliary or starting trode 12, also of mercury. The storage tery 13 to be charged is connected throu, switch 14 to the mercury cathode 11 an also connected to a tap 15, located betw the two reactance-coils 6 and 7. A dou pole switch 16 is provided by which 1 starting electrode 12 may be connec through a resistance 17 to the line condur 5 and by which the mercury cathode 11 in; be simultaneously connected through a r sistance 18 with the tap 15.

With the parts in the position shown in t1; drawings the starting operation is as follows Switch 16 is closed to impress a voltage tween the mercury electrodes 11 and after which the rectifier is shaken slightly tr form a contact between these electrodes, thus permitting current to fiow from elertrode 12 to electrode 11 and then through resistance 18 and reactance 6 to line conducto' 4. When electrodes 11 and 12 separate, a incipient arc is formed between the two me cury surfaces and furnishes an excitation the cathodesurface, which enables a con panion arc to start from the anode 2. Tl reactance 6 discharges between electrodes and 1 1 the energy previously stored up therein by the flow of current from electrode 122. The action of reactance 6 and a similar action of reactance 7 keep the rectifier in a conduct ive condition by bridging over the small inr of. time in each cycle during which the current from the line conductors 4 and 5 is zero.

As soon as the flow of current takes place through the rectifier the reactive coil 8 draw down its armature 9, so that the direct-current voltage delivered by the rectifier is reduced to the desired magnitude. To sub stitute the load 13 for the resistance 18, the switch 14 is closed, thus connecting the storage battery in shunt with the resistance, after which the switch 16 is opened to cause 9,1] (1%10' 8,150 to dis;

" place tput to pass tin-hug BEST AVAILABLE COP le and connected to said source, means 1' impressing the normal voltage of said urce across said rectifier-anodes and before re rectifier starts, and automatic means for acreasing the voltage on said rectifier when rrent begins to flow therethrough.

2. In a system of electrical distribution, source of alternating current, a vaporrectihaving a plurality of anodes and a cath and connected across said source, a lowigc storage battery supplied with ourfrom said rectifier, and a reactance defor automatically decreasing the voltage :essed on said rectifier When current beto flow thcrethrough. In a system of electrical distribution, a rce of alternating current, a vapor-recticonnected to said source, means for using normal voltage of said source to start i rectifier, and means operable by the flow :aid current for decreasing the voltage imessed on said rectifier.

4. In asystem of electrical distribution, a )urce of alternating current, a vapor-recti- .er connected thereto, means for starting aid rectifier, a reactance-coil traversed by said current, and automatic means for increasing the reactive efiect of said coil when current floiivs through said rectifier.

5. In a system of electrical distribution, a source of alternating current, a vapor-rectifier connected to said source, a low-voltage load to be supplied with direct current from said rectifier, means for utilizing the normal voltage of said source to establish a flow of currentthrough said rectifier, and means 0perated by the flow of current through said rectifier for reducing the voltage of the direct current supplied by said rectifier to a value suitable for supplying said low-voltage load.

6. In a system of electrical distribution, a source of alternating current, avapor-rectifier connected to said source, means for util izing the normal voltage of said source to start a flow of current through said rectifier, a resistance-load for said rectifier at starting, means for substituting a battery-load for the resistance-load after the rectifier has started, and means operated by the starting-current of said rectifier for reducing the pressure impressed thereon by said source of alternating current.

In Witness whereof I have hereunto set my hand this 18th day of April, 1905.

ALEXANDER CHURCHIVARD.

Witnesses:

BENJAMIN B. HULL, HELEN ORFORD. 

